Effects of Wet Removal on Aerosol Mass and Chemical Composition

CHRISTOS STAMATIS, Graham Frazier, Raina Lenear, Gabriel Isaacman-VanWertz, Virginia Tech

     Abstract Number: 480
     Working Group: Aerosol Chemistry

Abstract
A substantial fraction of secondary organic aerosol (SOA) is formed through the multigenerational oxidation of reactive organic gases. Therefore any processes such as wet and dry deposition that remove gases, in particular lightly oxidized and/or condensable gases, will affect the thermodynamic equilibrium and thus the formation and concentration of SOA. Unfortunately, the few direct observational constraints on the fate of oxygenated gases and particles and the timescales of wet removal lead to significant uncertainty in effects of precipitation on aerosol formation and properties. In this work we will present preliminary findings from the analysis of particle and precipitation size distribution data from several globally distributed sites in the Department of Energy Atmospheric Radiation Measurement (ARM) network as well as data from collocated measurements of wet scavenging of particles and gases collected in Blacksburg, Virginia using a semi-volatile thermal desorption aerosol gas chromatograph (SV-TAG) and laser disdrometer. Studying the real-world measurements from these diverse geographical locations will lead to an improved understanding of how precipitation affects aerosol chemical properties and mass as well as reduce uncertainties in regional and global models by introducing improved constraints on wet deposition of oxygenated gases.